Thermostat and thermostatic control device



E. J. ROHNE. THERMOSTAT AND'THERMQSTATIC CONTROL DEVICE.

APPLICATION FILED JUNE 10, 1920.

Patented Nov. 7, 1922;

Patented Nov. 7, 1922.

UNITED STATES EVEN J. BOHNE, OF MINNEAPOLIS, MINNESOTA.

THEBMOBTAT AND 'IHERMOSTATIC CONTROL DEVICE.

Application filed June 10, 1920. Serial No. 388,071.

To all whom it may concern:

Be it known that I, Evan J. RonNa, a citizen of the United States, and aresident of Minneapolis in the county of Hcnnepin and State ofMinnesota, have invented certain new and useful Improvements inThermostats and Thermostatic Control Devices,

of which the following is a specification.

One object of my invention is to provide in a thermostat improved meansfor breaking a contact so as to provide a longer break. Another objectis to provide improved means for controlling circuits in a heatingdevice.

With these and incidental objects in view,

section taken on the line 2-2, Figure 1;v

Figure 3 is a plan view of a fiat iron with the cover removed, showingform of thermostat and my improved circuit; Figure 4 is a wiring diagramofth device shown. in Figure 3.

As shown in the drawing, the frame 1 :is of general channel section, andterminal blocks 2 and 3 are provided at each end thereof.

Headless screws 4 and 5 pass through the two terminal blocks and areclamped thereto by nuts 6.

Contact bars 7 and 8 are mounted loosely on the studs 4 and 5 throughsuitable apertures, and oppositely disposed arch-shaped thermostaticelements 8, 9, 10, i1, and 22 are similarly mounted on the studs 4 and 5Contact screws 13, is, 15, and 16 are provided to co-operate with thecontact bars 7 and 8 Springs 17 are provided for clamping the contactbars and thermostatic elements together.

it is apparent that as the thermostatic elements straighten out underincreased temperature the contacts will be opened and numerous circuitsmay be controlled through the four contacts provided.

As the arch-shaped elements straighten out it is evident that a biggerbreak will be made at the contacts than if the action was controlled bya single thermostatic element.

a modified In the view shown in Figure 3 the flat iron 18 has a heatingelement 19 comprised of three separate circuits.

The thermostat comprises two thcrmo static elements 20 and 21, ofunequal length, and contacts 22 and 23 are provided for the thermostaticelements.

In wiring up the circuit the outside connection would be made to studs24 and 25, and one of the three coils of the heating element 19 would bepermanently attached to these terminal posts.

One of the other coils would be attached from the ost 24 to the contactscrew 22, and the third coil would be connected from the terminal post24 to the contact screw 23.

This is better shown in Figure 4, in. which the outside circuit isrepresented b ccnductors 26. One coil 27 is connecte from the terminalpost 24 to contact 22, the second coil 28 from the terminal ost 24 tothe contact 23, and the third coil 29 is connected from the terminalpost 24 to the terminal post 25, so as to be always in circuit when theflat iron is in use.

Inasmuch as the thermostatic elements are of different lengths, thecontacts are naturally open at different degrees of temperature.

While I have illustrated it in one particu ar design, I do not wish itunderstood that I limit myself to this construction, as it isevidentthat the application of the invention may be varied in many ways withinthe scope of the following claims:

1. in a thermostat the combination of a iramc, two oppositely disposedterminal minal blocks, a plurality of oppositely disposed arch shapedthermostatic elements oosely carried by said studs, through.apertures-in said thermostatic elements, and contacts for saidthermostatic elements, and resilient means for cl ampingsaidthermostatic elements together. v I

3. In a thermostat the combination of a frame, two oppositely disposedterminal i 85. described m'y inventimi and -'shaped thermostatic blocks,a plurality of oppositely disposed arch-shaped thermostatic elements,means carried by said terminal blocks for supporting said elements, andcontacts for said thermostatic elements.

4. In a thermostat the combination of a frame, two oppositely disposedterminal blocks, studs connecting said terminal blocks,

contact bars loosely mounted on said studs, a plurality of oppositelydisposed archelements loosely mounted on said studs intermediate of saidcontact bars, and a plurality of contact points carried by said terminalbars and with said contact bars. Y

6. The combination with a thermostat having a plurality of thermostaticelements of differing lengths, and a contact point for each of saidelements, of a plurality of circuits, including heating coils, one ofsaid circuits being connected across the direct terminals of saidheating device, and the other of said circuits being connected on oneside to one of the terminals of the heating device, and the other endsto said contacts whereby said heating coils will be controlledindependently by the individual thermostatic elements. 1 J

EVEN J. ROHNE.

coacting,

